As California and the U.S. move to become carbon-neutral, there are two forms of energy transmission that must be expanded. These are electricity generated from renewable sources such as wind, geothermal and solar, and hydrogen gas generated from direct hydrolysis of water or obtained from the breakdown of fossil fuels with carbon capture. Hydrogen will play an important role as a fuel for transportation as well as a storage medium for electrical power generation to buffer the inevitable fluctuations of solar and wind energy.
More than a century ago, the gas distribution network in New York City was developed to transport hydrogen. Only after World War II, when the national gas network became interconnected, was the switch made from hydrogen to our current pipeline network transporting natural gas.
The geological production of natural gas such as methane includes a small percentage of hydrogen gas, so even the current distribution network is adapted to transport hydrogen. Hydrogen will become the green fuel for marine transportation, which requires as much energy as does land transportation. Hydrogen can be mixed with natural gas since it is compatible for use in the same turbines and fuel cells as methane.
This ability to convert from natural gas to hydrogen is being undertaken by German firm Uniper Inc. to convert a liquid natural gas terminal into a national hydrogen hub. We have the ability to remodel gas transportation networks to transport hydrogen, which is fortunate given the obvious role that hydrogen will play in our energy future.
A California mandate calls for zero-emission vehicles by 2035. There are two kinds of zero-emission vehicles: battery-electric and hydrogen-electric. Both types of cars, with improved batteries and with hydrogen fuel-cells (such as the Toyota Marai), are needed to meet the zero-emission mandate.
The limited availability of hydrogen gas is currently a factor limiting the market for hydrogen fuel-cell cars, but hydrogen is rapidly taking over the truck and bus market as it provides flexible tank capacity, greater range and lower purchase cost, with no expensive batteries to be replaced in four to six years. The undersupply of hydrogen can be changed with the development of technology for removing the carbon from methane leaving the hydrogen.
The European Union is developing this technology, and Infineon Technologies Inc. has announced it will develop similar technology, created by the University of California Santa Barbara, for carbon removal from natural gas. This promises to allow inexpensive conversion of natural gas into hydrogen with carbon capture, a truly major breakthrough.
The recently canceled Keystone XL pipeline from Alberta to Oklahoma provides an opportunity to assist the adoption of a hydrogen economy if it were to be redesigned as a hydrogen gas pipeline. Canada’s desire was to send Syncrude from Alberta tar sands to Oklahoma and then on to global trans-shipment. Tar sands have been under development for more than 60 years, and the Keystone XL pipeline was critical to Canada’s attempts to introduce tar sand-derived oil to the global market. An alternative use of the tar would be to convert it into hydrogen gas and run a gas pipeline to interconnect with the U.S. network. This would have long-range benefits such as more hydrogen for electricity generation, and for direct use as a transportation fuel. Current pipelines can handle mixtures of hydrogen and natural gas up to 95 percent hydrogen and both current turbines and fuel cells function with this range of mixtures.
Tar from sands can be converted into hydrogen by a water-gas process; by burning and applying water or by a catalytic process. Resulting carbon dioxide could be injected into wells for sequestration. Wood to make bio-fuel hydrogen could become an important component of the hydrogen supplied by Canada’s wood reserves. The net effect would be to make Canadian hydrogen 100-percent green and provide Canada and the U.S. with hydrogen, and substantially advance North American green energy goals.
We could have much-needed hydrogen to fuel power plants formerly using fossil fuels then providing green electricity for electric automobiles. Canada’s hydrogen production center may provide an example for the greening of North America and come about 10 years sooner than our 2035 zero-emission vehicle goal. It might induce U.S. oil companies to process their methane production into hydrogen, making the 30 percent of electric power produced by natural gas to become green sooner. Re-negotiating with environmental objectives for a new replacement pipeline could be a very productive opportunity. Why throw it away?
Robert Rex is a research associate geochemist at Scripps Institution of Oceanography at UC San Diego. He was previously the CEO of Republic Geothermal Energy, a Chevron research scientist, and served on the Presidential Energy Advisory Committee during the Nixon Administration.